The Biological Effects of Solitary Confinement

by S.M. Asiedu

            Of the over two million people incarcerated in the United States there are over 80,000 prisoners held in solitary confinement (Keim, 2013).  Cells average six by eight feet in size and inmates are locked in 23 hours a day (Keim, 2013). Prisoners are held for years or decades with almost no human contact and minimal sensory stimuli (Keim, 2013). 


            Solitary confinement originated in Europe and North America in the 19th century with the aim of reforming convicts through isolation (Shaley, 2008, p.2).  Entire prisons penitentiaries were built to house people individually in solitary (Shaley, 2008, p.2). Instead of reform, this practice caused inmates to become mentally ill (Shaley, 2008, p.2).  By the late 19th century, this system was brought to an end, but solitary confinement was not; solitary confinement was still in use in prisons worldwide as a form of short term punishment, political prisoners, protective custody, and as a way of “softening-up” detainees during the process of their interrogation (Shaley, 2008, p.2).

            At the end of the 20th century, large scale solitary confinement in the form of super-maximum security (supermax) prisons were built for the confinement of long term and strict isolation of high risk classified inmates (Shaley, 2008, p.2). 

Human Rights

            Human rights instruments designed for prisoners and detainees such as the two international treaties, the International Covenant on Civil and Political Rights (ICCPR) and the UN Convention Against Torture (CAT) are legally binding to those countries that signed them and their parallel regional instruments (Shaley, 2008, p.3).  These rights include “the right of prisoners to be treated in a manner respectful of their human dignity and the prohibition against all forms of torture, inhuman or degrading treatment or punishment” (Shaley, 2008, p.3). Solitary confinement deprives people of the use of their natural senses, their awareness of place and the passing of time and deprives individuals from human contact and interaction; all of these aspects of the experience of solitary confinement are indicated in the International Covenant on Civil and Political rights (ICCPR) as being violations (Shaley, 2008, p.4).  The United States signed this treaty in 1977 (ICCPR, 2014).

Health effects of solitary confinement

            Since the beginning of its use in the late 19th century, practitioners and researches have observed and documented the adverse effects of solitary confinement (Shaley, 2008, p.9).  “Prison Psychosis” was first termed in 1854 by the chief psychologist of Halle prison in Germany after observing isolated prisoners, concluding that “prolonged absolute isolation has a very injurious effect on the body and mind and seems to predispose to hallucinations” (Shaley, 2008, p.10; Keim, 2013).  Similar findings were reported in Europe and the United States throughout the 19th and 20th centuries (Shaley, 2001, p.10-11). 

            Solitary confinement negatively effects health and wellbeing, especially for individuals with pre-existing mental health disorders (Shaley, 2008, p.10; Keim, 2013).  There is evidence that solitary confinement itself causes mental illness and absolutely no evidence reporting positive effects (Shaley, 2008, p.10).  

            Physiological effects may be psychosomatic or due to lack of fresh air and natural light as well as long periods of inactivity (Shaley, 2008, p.15). The physiological effects reported from various studies were as follows: gastro-intestinal, cardiovascular and genito-urinary problems, migraine headaches, profound fatigue, heart palpitations, diaphoresis, insomnia, back and other joint pains, deterioration of eyesight, poor appetite, weight loss, diarrhea, lethargy, weakness, tremulousness, chills, and aggravation of pre-existing medical problems (Shaley, 2008, p.15).

            The psychological effects differ depending on how the individual adjusts to confinement, their pre-existing mental health status and the context, length and conditions of confinement (Shaley, 2008, p.15).  Individuals with trauma histories are more vulnerable to adverse psychological effects of solitary confinement and initial acute reactions may follow with chronic symptoms if confinement is long-term (Shaley, 2008, p.15). 

Psychological effects reported include the following:

Anxiety, ranging from feelings of tension to full blown panic attacks

persistent low level of stress
irritability or anxiousness
fear of impending death
panic attacks

Depression, varying from low mood to clinical depression

Emotional flatness/blunting – loss of ability to have any “feelings”
Emotional lability (mood swings)
Social withdrawal; loss of initiation of activity or ideas; apathy; lethargy
Major depression

Anger, ranging from irritability to full blown rage

Irritability and hostility
Poor impulse control
Outbursts of physical and verbal violence against others, self and objects
Unprovoked anger, sometimes manifesting as rage

Cognitive disturbances, ranging from lack of concentration to confused states

Short attention span
Poor concentration
Poor memory
Confused thought processes; disorientation

Perceptual distortions, ranging from hypersensitivity to hallucinations

Hypersensitivity to noise and smells
Distortions of sensation (e.g. walls closing in)
Disorientation in time and space
Hallucinations affecting all five senses, visual, auditory, tactile, olfactory and gustatory (e.g. hallucinations of objects or people appearing in the cell, or hearing voices when no-one is actually speaking)

Paranoia and Psychosis, ranging from obsessional thoughts to full blown psychosis

Recurrent and persistent thoughts (ruminations) often of a violent and vengeful character (e.g. directed against prison staff)
Paranoid ideas – often persecutory
Psychotic episodes or states: psychotic depression, schizophrenia.

(Shaley, 2008, p.15-16)

Self-harm and suicide

              Self-harm, such as cutting or banging ones head against the cell wall, are more common in isolation units than the general population of the prison (Haney & Lynch, 1997 as cited by Shaley, 2008, p.17).  According to a study by the Bureau of Justice Statistics found that over fifty percent of incarcerated people have mental illness, four times the rate in the general population (Horowitz, 2013).  69% of suicides occurred in solitary confinement as reported in California by USA Today in 2006 (Shaley, 2008, p.17).

            Symptoms of solitary confinement have been compared to those of soldiers with Posttraumatic Stress disorder, in which prolonged stress alters brain pathways (Keim, 2013)


Etiology of Symptoms

              Social isolation, reduced environmental stimulation and complete powerlessness are the main factors that causing distress as a result of solitary confinement (Shaley, 2008, p.17).

Social isolation

              Prolonged social Isolation can lead to further withdrawal after release from prison; this can undermine their ability to adjust to society (Shaley, 2008, p.18). Research concerning the neuropsychological effects of social exclusion found that the brain is activated in areas “shown to respond specifically to the affective dimension of physical pain experience”, the dorsal cingulate cortex and the right ventral prefrontal cortex (Nordgren, Banas & MacDonald, 2011, p.120).  In response to recalling experiences of social loss, endogenous opioids decrease in response; endogenous opioids are known for their role in reducing physical pain (Nordgren et al., 2011, p.120).

Reduced environmental stimulation

              Reduced activity and stimulation reduces brain activity which “correlated with apathetic, lethargic behavior… and with a reduction of stimulation seeking behavior. Up to seven days the EEG decline is reversible” (Scott & Gendreau, ibid., as cited by Shaley, 2008, p.20).


              The high level of control over all aspects of the individual while in solitary confinement produce reactions from apathy, listlessness, irritability and nervous instability, over time “likely to mature into either homicidal or suicidal behavior” (McCLeery, 1961, 265, as cited by Shaley, 2008, p.20). 

Long lasting effects of solitary confinement

              Studies have reported the following symptoms long after release from isolation: sleep disturbances, nightmares, depression, anxiety, phobias, emotional dependence, confusion, impaired memory and concentration, intolerance to social interaction, paranoia and an inability to trust others (Shaley, 2008, p.22).

Effects of solitary confinement on juveniles

              The adolescent brain is still undergoing major structural growth, particularly in the frontal lobe, responsible for cognitive processes (Dimon, 2014).  The dorsolateral prefrontal cortex continues to develop in humans through their twenties and is linked to inhibition of impulses and the consideration of consequences (Dimon, 2014).  When juveniles are placed in solitary confinement, it is damaging to the development of their brains (Dimon, 2014). There are around 70,000 incarcerated juveniles in the U.S., of which 63% are there for nonviolent crimes (Dimon, 2014).  More than half of juvenile offenders have been held in isolation for over 24 hours (Dimon, 2014).


              Many children and adults come into the criminal justice system with complex trauma histories.  Solitary confinement is the prison response to all offenses no matter how small – an extra candy bar in the cell or a wrong word to a prison guard is all it can take to be put in “the hole” for an indeterminate time until the “disciplinary committee” takes place.  The neurological damage caused by incarceration and solitary confinement perpetuates criminal activity by economically and socially vulnerable people.

              Although neurological effects of solitary confinement are important to continue to research as they help support its abolition and direct mental health professionals to develop more effective treatment for this population, there is no absence of evidence of the barbarity of this practice.   

               The bottom line is that the government DOES NOT CARE, and correctional institutions overwhelmingly are not held to ANY standards.  


               What can you do as a concerned human being? Go and visit someone in your local prison, put bodies in the visiting room.  All you need is someone's name and an i.d.  To get involved, check out "Love Destroys Razor Wire", 

                If you have been incarcerated and experience these symptoms, you are NOT CRAZY. These are normal reactions to isolation.  If you need help, we here at DEEPROGRAMMING understand where you're coming from. First consultation is free for formerly incarcerated people. 


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